SPECIES DELIMITATION WITHIN THE BOUTELOUA GRACILJS- B. HIRSUTA- B. PECTINATA COMPLEX

by WILLA FA YE FINLEY, B.S. A THESIS IN BOTANY

Submitted to the Graduate Faculty of Texas Tech University in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE

Approved

Accepted

May, 1977 7 '^

// ^ , V '^- ACKNOWLEDGEMENTS

I would like to thank Dr. D.K. Northington for his help and role as committee chairman as well as the other members of my committee, Dr. R.E. Sosebee and Dr. J.R. Goodin, for their help and for reading the manuscript. Thsinks must also be extended to the following graduate students for their as- sistance--Tony Burgess, Gary Jahns, Brent Davis, Jim Hallet, and Larry Hilbum. Thanks and appreciation are due Gary Finney and LaShara Nieland for preparing plates and line drawings. Use of land and travel funds from the Texas Tech Museum is acknowledged. Acknowledgement is made to the following herbaria and their curators from which specimens were borrowed: University of Arizona .(ARIZ), Kansas State University (KSC), University of Mexico (MEXU), University of Nebraska (NEB), New Mexico State University (NMC), University of Oklahoma (OKL), Oklahoma State University (OKLA), Southern Methodist University (SMU), Texas A&M University (TAES), University of Texas (TEX), and U.S. National Herbarium (US).

11 TABLE OF CONTENTS

ACKNOWLEDGEMENTS ii ABSTRACT iv LIST OF TABLES v LIST OF FIGURES vi CHAPTER

I. INTRODUCTION 1 II. TAXONOMIC HISTORY 3 III. CYTOGENETIC REVIEW 7 IV. FLAVONOID CHEMISTRY 9 V. MORPHOLOGY 19 VI. TAXONOMIC TREATMENT 33 LITERATURE CITED f,!

Ill ABSTRACT

Bouteloua gracilis. B. hirsuta, and B. pectinata were examined for evidence of present hybridization based on presence of "intermediate" populations occurring in the vi­ cinity of Guadalupe Mountains National Park. To establish the nature of the relationships more clearly, flavonoid ex­ tracts of members in question were chromatographed and a series of morphological characters were measured and analyzed using multivariate techniques. No evidence for on-going hybridization was obtained; however, ancient hybridization between B. pectinata and B. gracilis may account for the morphological traits of "inter­ mediate" populations. Commonly used dichotomous keys used to distinguish among the three species were found to be inade­ quate. A more workable alternative was presented.

IV LIST OF TABLES

Table 1. Color, color change, and Rf values of flavonoid compounds of B. gracilis, B. hirsuta, and B. pectinata 15 2. Frequency of presence of flavonoid compounds .... 17 3. Location and location number of species examined in flavonoid and morphometric analyses 26 ^. Means of 11 variables (for number of cases indicated) computed from raw data for each of 18 populations 29 5. Pooled within groups correlation matrix computed from raw data for 18 populations and 11 variables 30 6. Variables used in initial discriminant analysis . , , 3I 7. Coefficients for canonical variables 32 LIST OF FIGURES

Figure 1. Distribution map of B. gracilis. B. hirsuta, and B. pectinata 6 2. Composite chromatogram of flavonoid compounds from B. gracilis. B. hirsuta, and B. pectinata ... 12 3» Individual chromatograms of flavonoid compounds. . . 1^ 4. Three-dimensional plot of factor scores for B. gracilis, B. hirsuta, and B. pectinata 25 5. Drawing of B. hirsuta ^7 6. Drawing of B. gracilis ^9 7. Drawing of B. pectinata 51 8. Drawing of spikelets of B. gracilis, B. hirsuta, and B. pectinata 53

VI CHAPTER I Introduction

Among the 16 species of the genus Bouteloua (Gramineae) that are present in the state of Texas are three closely related members--B. gracilis (H.B.K.) Lag. ex Steud. (as per Chase, 1951)t B. hirsuta Lag., and B. pectinata Featherly. Populations sharing characteristics of B. gracilis and B. hirsuta occur in the vicinity of Guadalupe Mountains National Park. These characteristics include short rachis extension and heavy tuberculation of second glume, typical of B. hirsuta; and the glume-like nature of the rachis projection, more robust habit and height typical of B. gracilis. Hybrid­ ization between B, gracilis and B. hirsuta was proposed by this author as the explanation for the presence of these populations. Examination of another member of this genus, B. pectinata, was deemed necessary as a consequence of certain morphological similarities to the putative B. gracilis- B. hirsuta hybrid, e.g., more robust habit, elongation of rachis with presence of terminal glume on rachis, and heavy tuberculation of second glume. Correll and Johnston (1970) have proposed that ancient hybridization between B. gracilis and B. hirsuta var. pectinata (B. pectinata) accounts for the occurrence of this "intermediate" group. 1 Flavonoid chromatography and multivariate analysis of a series of morphological characters were proposed as means for elucidating the nature of this relationship. CHAPTER II Taxonomic History

Griffiths (1912) and Chase (1951) give a comprehensive summary of published notes and descriptions of B. gracilis, B. hirsuta, amd B. pectinata. Based on examination of avail­ able early descriptions no nomenclatural problems were apparent. Lagasca published the first valid description of B. hirsuta in 180^. The valid name B. gracilis (H.B.K.) Lag. ex Steud. was published in 1840 based on Chondrosium gracile (H.B.K.). B. pectinata was not considered a distinct species until 1931 when Featherly published a valid description. A varie­ tal name, B. hirsuta var. major, was given by Vasey to a plant collected by Stiles in 1884 (US 8O3032) but a descrip­ tion did not accompany the publication. Featherly (I93I) felt that Vasey's drawing did not accurately represent the plant, and accordingly published a description with the spe­ cific epithet pectinata. Cory (I936) reduced B. pectinata to varietal status--B. hirsuta var. pectinata--with no accompany ing explanation. However, F.W. Gould annotated US 8O3032 as B. pectinata in 1970, and Roy and Gould (1971) recognize B. pectinata at species level. 3 The geographical range of each species was determined from herbarium sheet localities and is presented in Fig. 1. Type specimens examined from the U.S. National Herbarium include US 78O67, B. hirsuta var. minor Vasey (I89O); US 78068, B. hirta (has inflorescence branch of B. gracilis in remnant folder); US 78O69, B. palmeri Vasey which is not typical of B. hirsuta (too tall, culms too thick, and inflo­ rescence branches too long, which may simply be due to the fact that it is cultivated; US 8O3032, B. hirsuta var. ma.jor Vasey, annotated by F.W. Gould in 1970 as B. pectinata; US 78070, B. hirsuta (lectotype, see Chapter VI); a xerox photo of Atherpogon oligostachyus Nutt. (unnumbered) is the type of this epithet, but may not be typical of B. gracilis-- a note attached to the sheet says "glumes long-pilose", but difficulty was encountered in making a judgment based on such scanty information. An isotype of B. pectinata Featherly (OKLA 1307) was also examined. Except as noted, these speci­ mens are representative of their respective species and correctly identified.

Fig. 1. Distribution map of B. gracilis, B. hirsuta, and B. pectinata B. gracilis B. hirsuta B. pectinata (\\\\\\)

CHAPTER III Cytogenetic Review

In view of the facts that chromosomes of B. gracilis, B. hirsuta. and B. pectinata are extremely small and diffi­ cult to count, and that several individuals have reported chromosome numbers without a conflict in counts, previously published counts were accepted as accurate. Fults (1942) assumed the base chromosome number for B. gracilis to be x=7 and reported 3N, 4N, 5N, and 6N counts as well as two localities with 2N=6l and 2N=77. Chromosome counts for B. hirsuta were given as 2N=21, 37, and 42. Snyder and Harlan (1953)» however, reported a base number of x=10 for the genus Bouteloua, with counts of 2N=20, 40, and 60 reported for B. gracilis. They explain that counts reported by Fults are probably the result of aneuploidy through non-disjunction, or that aneuploidy arose at the diploid level and was perpetuated by polyploidy. In addition, aneuploid chromosome numbers of 2N=24,36,46, and 48, as well as 2N=20, 40, and 50 for B. hirsuta and hy­ brids between B. hirsuta and B. pectinata were reported by Roy and Gould (1971)• B. pectinata consistently had chromo­ some numbers of 2N=20. Reports of x=10 by Snyder and Harlan (1953) and Roy and Gould (1971) for the three species appear to be adequate 7 8 evidence that Fulfs original report of x=7 is inaccurate. There is no reason to doubt that polyploid and aneuploid ser­ ies as reported are correct. CHAPTER IV Flavonoid Chemistry

Chromatographic techniques used follow those of Mabry, Markham, and Thomas (1970). Leaves were dried and crushed; flavonoids were extracted in 85^ methanol for 48 hours. The extract was spotted on Whatman 3 MM chromatographic paper; chromatograms were developed in solvent systems of tertiary butanol, glacial acetic acid, and water (3:1:1, v/v) for the first dimension and 15^ glacial acetic acid for the second dimension. Resultant spots were measured for Rf values and observed under UV light alone and in presence of ammonia va­ pors for color characteristics. A composite chromatogram is presented in Fig. 2; Fig. 3 contains individual chromatograms for the three species. Rf values and color/color change are presented in Table 1; presence/absence of spots are presented in Table 2.

Eleven specimens from three populations (2, 7f and 15) of B. gracilis; 14 from four populations (4, 8, 11, and 17 of !• hirsuta; and eight from two populations (6 and 9) of B. pectinata were used for flavonoid extractions. Selections for extraction were made on the basis of sufficient leaf ma­ terial. Population numbers are presented in Table 3* Each species had several spots which were present only in that species. Compound numbers 16, 18, 19, 27» 29, and 31 10 were present only in B. hirsuta; 21, 22, 23, 30, and 32 were found only in B. gracilis; and 17, 20, 24, and 25 were present only in B. pectinata. Rf values of Compound numbers 1, 3, 4, 9, 10, 13, 14, 18, and 19 indicated that they probably are C-glycosides (Mabry, Markham, and Thomas, 1970). Another complicating factor involves heterogeneity in patterns within plants and within populations. Flavonoid analysis was not pursued fur­ ther for these reasons. 11 Fig. 2. Composite chromatogram of flavonoid compounds from B. gracilis, B. hirsuta, and B. pectinata IL^

DVOH 13 Fig. 3' Individual chromatograms of flavonoid compounds A. B. gracilis B. B. hirsuta C. B. pectinata ]•}

DVOH

< 9? © CO CN CN CN 0® G ® ^ Q CN (p© G DVOH O © < o ^ OQ ^ H- o 6 Q 9^0 CN 0 2-^ K ro (d ©IQ pq

>0 00 6 >0 "7 CN CNI

CN

lO DVOH <^ CN < oo n o 0

C^ ©

o o CN •o CM CM e ^s! (b 15 TABLE 1. Color, color change, and Rf values of flavonoid compounds of B. gracilis, B. hirsuta, and B. pectinata

COMPOUND COLOR COLOR Rf NUMBER UV UV/NH^ TBA HOAC

1 FB NC .18 .08 2 P Y .60 .02 3 P YG .11 .44 4 P OY .20 .29 5 P YG .3^ •35 6 P YG .44 .^3 7 P YG .28 .58 8 P YG .32 .71 9 P Y .27 .10 10 P Y .05 .14 11 P YG .37 .59 12 I B .39 .14

13 P YG .25 .18 14 P OY .07 *26

15 I B .78 .12 16 P PK .73 .32

17 P BG .42 .26 18 P YG .17 .49 19 P DY .11 .20 20 P BG .41 .75 Table 1. (continued) ^^

COMPOUND COLOR COLOR Rf NUMBER UV UV/NH^ TBA HOAC

21 P YG .51 .56 22 P BG .13 .78 23 P Y .13 .67 24 P NC .77 .18 25 I B .84 .44 26 I B .78 .50 27 B BB .84 .54 28 P NC .74 .23 29 P NC .84 .26 30 P Y .31 .29 31 P YG .20 .58 32 P DY .31 .52

B=blue, BB=bright blue, BG=blue-green, DY=dull yellow, FB=flourescent blue, I=invisible, NC=no change, 0Y=orange- yellow, P=purple, PK=pink, Y=yellow, YG=yellow-green 17 TABLE 2. Frequency of presence of flavonoid compounds.

COMPOUND NUMBER B. gracilis B. hirsuta B. pectinata

1 ••• ***

2 ••• *** 3 •••

4 «««

5 ••• •••

6 •• •••

7 •• •••

8 ***

9 ••• •••

10 *** »•

11 **

12 ** **

13 14

15 16

17 18 19 20 18

COMPOUND NUMBER B. gracilis B. hirsuta B. pectinata

21 •• 22 •N-

23 * 24 *

25 *«

26 ** *** ««

27 «# 28 **

29 •• 30 •* 31 •N--N-N- 32 • •*

***=present in all specimens examined **=present in at least 50^ of specimens examined *=present in less than 50% of specimens examined CHAPTER V Morphology

Plant material for this study was collected in August, September, and October, 1975. from 18 localities within Texas and New Mexico. Location, location number, and species col­ lected from each locality are listed in Table 3. Data were taken from three flowering culms (in peak bloom) per plant to allow for morphological variability with­ in individual plants. Total number of cases from each population are given in Table 4. Means and a correlation matrix for 11 variables were computed from raw data with the aid of SIMPLE (Gaskins, 1975). These data are presented in Tables 4 and 5. Means were sig­ nificantly different at the O.O5 level. Correlation among characters was very low, indicating that the variables se­ lected yielded independent information. Multivariate techniques have been used to determine taxonomic affinities of species involved. A stepwise dis­ criminant analysis program, BMD-P7M (Dixon, I975), was employed to determine whether populations would separate ac­ cording to a priori-designated species or if population differences existed such that species affinities would not be clearly recognizable. Morphological data were initially taken from I7 structures which intuitively appeared to have greatest discriminatory power. These variables are listed in

19 20

Table 6 gind include two structures commonly used to distinguish B. hirsuta and B. pectinata from B. gracilis--rachis projec­ tion as a bristle in B. hirsuta. rachis projection terminating in a glume-like structure in B. pectinata, and absence of ex­ tension or a glume-like projection in B. gracilis; and presence of papilla-based hairs in B. hirsuta and B. pectinata and lack thereof in B. gracilis. Also included were char­ acters used by Roy and Gould (1971) in distinguishing B. hirsuta from B. pectinata--length of longest basal leaf, in­ florescence length, number of inflorescence branches, and anther length. Of these four, inflorescence length was elim­ inated in the multivariate analysis (univariate analysis was used by Roy and Gould). Stepwise discriminant analysis also included five characters which Roy and Gould (1971) excluded in their analysis--length of rachis projection beyond termi­ nal spikelet, length of spikelets, length of first glume, length of second glume, and length of rudimentary floret. Variables 1-17 were subjected to a stepwise discriminant prograjn which indicated that on the basis of significant F-values, 11 variables were of greatest value in separating groups. These are numbered 1-11 in Table 6. Transformations of the 11 variables were made with the natural log in order to reduce variance heterogeneity by re­ moving effects of measurement units. Homogeneity of variance was achieved only when Variable 6 was removed from considera­ tion. However, since its importance in discrimination is 21 evident from BMD-P7M, it was included in all analyses in spite of its heterogeneity of variance. The first four discriminant functions are effective in maximizing group differences, as indicated by the relative proportion of the first four eigenvalues--57-5?^, 27-0^, 7-6^, and 3.2^. A plot of the first two canonical variables eval­ uated at group means reveals distinct separation of the 18 groups into three groups corresponding to species designation. Discriminant Functions One and Two therefore achieved par­ simonious separation of the 18 groups. Coefficients for the canonical variables were standardized by multiplying by the pooled standard deviation for each var­ iable in spite of the fact that effects of measurement units should have been eliminated by transformation of data. Both raw and standardized coefficients are presented in Table 7 and Indicate that the first discriminant function maximized differences between group means on the basis of Variable 3* The second discriminant function coefficients show separation on the second axis on the basis of Variables 1, 5» 6, 8, and 9. Variables 1 and 6 appear again with high values in the third discriminant function, while the fourth discriminant function shows separation based on Variable 8. A classification matrix which gives an actual count of number of cases classified into each population shows that 1.4?S of total entries was misclassified (i.e., outside a priori species classification). One population of B. 22 pectinata (9) had two members misclassified as B. hirsuta (4, 8); one population of B. hirsuta (8) had four members misclassified as B. gracilis (1, 15); Population 1 of B. gracilis had one member misclassified as B. pectinata (9); and another B. gracilis population (14) had 1 member mis­ classified as B. hirsuta (13). BMD-P7M also generated an F-matrix used to test significant differences between any two group means. All group pairs were significantly different from each other for •^=0.01, with 11 and 551 degrees of freedom. An evaluation of the preceding analyses indicates that even though populations grouped together in a priori desig­ nated species, each population maintains a distinct morphological identity. Forty-five cases were entered into BMD-P7M as ungrouped data. Only one was misclassified: a specimen of B. gracilis ( Pop. 1) was misclassified as B. pectinata (9). and was the same specimen that had been misclassified in the original classification matrix. Mahalanobis distances between populations were computed from transformed data with the SAS program (Barr et. al., 1976) and entered into the TAXON. FACTOR, and MST programs from the NT-SYS package (Rohlf et. al., 1972). TAXON com­ puted a phenogram from the input matrix which showed separation of the data into three groups corresponding to designated species. FACTOR computed three factor scores for 23 each group from a principle coordinates analysis. These factor scores were used to construct a three-dimensional plot (Fig. 4). Most-closely-related pairs of groups were identi­ fied with MST (minimum spanning tree) and connected by a line. The eight groups of B. hirsuta are separated on Axis I; three groups of B. pectinata separate from the seven groups of B. gracilis on Axis II. Groups 5 and 6 of B. pectinata are dis­ tinct from Group 9 on Axis III; Groups 2 and 7 of B. gracilis are separated from other B. gracilis groups on Axis I; whereas Group 4 of B. hirsuta is separated from other B. hirsuta groups on Axis II and III. Minimum spanning tree lines connect B. pectinata to B. gracilis through 9 and 1. while B. pectinata is connected to B. hirsuta through 9 and 4. B. pectinata thus shares characteristics with both B. gracilis and B. hirsuta, and provides the only link between the latter two species. Since Fig. 4 expresses identical in­ formation obtained from TAXON and the BMD-P7M plot, and does so most concisely and clearly, it is the only one presented in this work. 24 Fig. 4. Three dimensional plot of factor scores for B. gracilis (1, 2, 7, 14-17), B. hirsuta (3, 4, 8, 10-13, 18), and B. pectinata (5, 6, 9). Most' closely-related pairs are connected by minimum spanning tree lines. 25

U

H 26

TABLE 3. Location and location number of species examined in flavonoid and morphometric analyses.

POPULATION SPECIES NUMBER LOCATION

B. gracilis TEXAS. Brewster Co., O.5 mi SE from JCT of US 90 and US 67. clay-loam soil. NEW MEX.Lea Co., 2.0 mi SW from JCT of US 62 and NM I76. clay- limestone soil. TEXAS. Floyd Co., 0.2 mi W. from JCT of FM 97 and FM IO65. sandy loam. 14 Jeff Davis Co., 3.2 mi NW from JCT of TX 118 and TX 17. red loamy clay.

15 Hudspeth Co., 0.7 mi S. from JCT of FM 1111 and US 80. clay-caliche soil.

16 El Paso Co., 34.1 mi W. from JCT of FM 1111 and US 62. sandy soil.

17 Culberson Co., 7.8 mi W. from JCT of US 180 and FM 1108.

B. hirsuta Taylor Co., 12.0 mi S. from JCT of FM 707 and US 277, then 0.5 mi E. on caliche road, sandy over limestone rocks. TABLE 3. (continued)

POPULATION SPECIES NUMBER LOCATION

Brown Co., 3*8 mi E. from Zephyr on FM 218. Roadcut through limestone hill. 8 Edwards Co., 6.3 irii W. from JCT of FM 674 and TX 377- Limestone bedrock overlain by thin layer of black clay.

10 Williamson Co., 4.8 mi S. from JCT of US I83 and TX 29, then 0.1 mi W. on caliche road.

11 Travis Co., 1.8 mi from NW end of Mansfield Dam on Pescado Circle. Clay over limestone.

12 Brewster Co., 16.7 mi E from JCT of US 90 and US 67. loamy clay with limestone rocks.

13 Brewster Co., 9*0 mi E from JCT of US 90 and US 67. clay soil with rocks.

18 Culberson Co., 7.8 mi W from JCT of US 180 and FM 1108 28

TABLE 3. (continued)

POPULATION SPECIES NUMBER LOCATION

B, pectinata Brown Co., 3*8 mi E from Zephyr on FM 218. Roadcut through limestone hill. 6 Travis Co., 1.8 mi from NW end of Mansfield Dam on Pescado Circle. Limestone and clay soil. Taylor Co., 12.5 mi S. from JCT of FM 707 and US 277, then 0.5 mi E. on caliche road. Sandy with lime­ stone rocks. 29

«M to O 0 to r-i xr\ o XA r-i O CA cr o 1 \ n • cd CVJ XA CA (A CNJ CA CNJ CA CVJ CA 1 a> o tj> 4-> 2 cd o •H rH 00 v£) NO XA XA (A CA ON 00 00 'd CNJ r-i .-1 r-i r-i r-i rH r-i rH f-i r-{ r-i CVJ r-i r-( r-i C •H O o o O O O O O o O O o O O O O o o o o O O O O o O O <-> o o to o o o o O o 0) (0 C\2 o 00 XA CVJ NO ON CTN r-i 00 CA NO ON (d CNJ CVJ CNJ rH CNJ CNl CVJ r-i CNJ •-i CNJ r-i CNJ CNJ r-i CNJ CVJ CNJ O O o o O O O o O O o O o O O O O o o CH • O o o O O o O O o O o O O o o o to o o o C (H o 00 CNJ r^ 00 CNJ 00 r- CNJ ON o NC o ON J- CTN CN- 0 •H U-N CVJ 00 ^ r-i CA O r-i r-t CVJ XA N£» ,0 4^ ON o B Cd CNJ CNJ CNJ (A CVJ CA CNJ CA CNJ CA CA CNl CNJ CNJ CM :3H O o O o o O O O O O O O O O O C :3 o o o Pu (^ o rH O 00 00 ts- 00 O IS- O XA NO CA o o P* CNJ r-i XA C7N CNJ r-i XA O NO O CNl CA o XA o «H 00 o oo CNJ CVJ 00 o o XA r-\ ^ XA J- XA NO rH NO CN- CA CA ^ N£) NO XA XA CA NJJ «H 0 O CNl o CNl CNl CNJ CNJ vO XA CNJ r-i CA XA iH CNJ CNJ CVJ CNJ CVJ CNJ CNJ CNJ CNJ CNJ CNJ CNJ CNl CNl CNJ CNl CNl ^ .c cd O o o O o o o O O O O O O O O O o O EH Cd 0 o o O o o o O O O O O O O O O Q) o o o

•cH S-. o r-v cn c*^ (A O 00 CNJ O o CA o o o r-\ XA 00 00 ON XA XA O TJ tH 0) Cd o o 00 00 r-\ CA XA CA CA 00 NO ON NO NO +J cd > o r^ H O r-i rH r-i r-i r-i r-i O O O o r-i to -P •H cd rH T3 rH ON 0^ xn xn ON NO r-i NO r-i 00 o ON -«.^' (A CA CA CA XA CA XA CA ? vn to cd o o o o o O o O O O o O o O O o O O 0 ^ O o o O o O o O O O o O o O O o O O iH ^ Cd oe ON 00 xo CNJ CNl CJN XA CNl C7N ON 00 NO 00 •H ^ xr\ XA XA XA XA XA XA XA XA XA ^H CH Cd O o o o O O O o O O o O O O o o O O > -d O o O o O O O o O O o O o o o O O 0 o rH -P rH ^ c*^ ON O r-i XA XA r-i ON 00 XA o o O P. o o NO r-i r-i O O 00 O vD 00 O o o O tV tH B r^ O o o o o o o O O O O o r^ O o O o o O o o o o o o o O O O O o O O o O o o O o to C cd 00 ON 00 ON 00 NO o O CNl ON o o XA r-i O tv 0) 00 NO ON 00 CNJ NO CA CVJ CA XA 00 r-i c\j o CVJ CVJ rH r-i CNJ CNJ (A r-i CNl r-i r-i CNl CNJ CNJ CNJ .-H o o O o o o O O O o O o o O o o O O

CVJ r-i 00 XTN NO XA 00 v£> CNJ XA XA CA r-i 00 C^ 0 o CNJ ON 00 0^ CVJ ON O 00 XA r-i XA {*"- c r-i o NO o CNJ o C?N (A ON O CNJ VA XA r-i o 00 o 00 Cd r-i r-i r-i rH CNJ CVJ r-i O CVJ r-i r-i O O r-i r-i r-l E-t o o

P< O r-i CNJ r-\ ^ vn vO C^ 00 ON o rH CNJ CA XA N^ cc O 2 r-i r-i rH r-l r-i ,-i rH r-i >—< 30

oO o 00

o CH O CJN O CNJ cd O +J cd 73 5 o c^ CA cd o o CJN CA r-{ u CTN o B o u «H O c^ C7N 00 o NO rH C^ T3 o NO r-i O 0 00 +;^3 • P^ to B 0 r-i O -H O ^ o cd ts- .00 0 .20 2 .21 2 .11 8 X •H H o o o o •H ^ ^^ cd +^ > O XA NO 00 C7N cd O r-i XA XA Br-\ O O T-i r-i O o r-i NO C r-i O o O O o O TJ •H C •P cd o ON ON c^ Cd o CA CVJ XTN o rH to o CVl CA CNl 0 c: XA .06 1 .20 4 ^ o rH o O o o O O JH •H o +J o cd O

.00 0 .21 8 .06 6 o ^-> rH o o o o o O o o •H 1

73 00 o o 00 CA 0 CNl CA CA XA CA XA O r-i O O O •-i O r-i O .00 0 .01 6 .04 4 .00 4 O rH o O O O o o O O o CU 1 1 1 1 1 I

O 00 (A CA XA o O CNJ NO NO CA XA O r-i O O O o r-i r-\ .02 1 .00 8 .09 3 w r-i O O O O o o o o o o 1 w m CNl CA XA NO 00 ON

-a; > 31

TABLE 6. Variables used in initial discrirr.inant analysis.

VARIABLE DESCRIPTION

1 Length of longest basal leaf 2 Number of inflorescence branches 3 Length of rachis projection 4 Length of spikelets, including awns 5 Length of second glume 6 Number of tubercles on second glume 7 Length of anther 8 Number of spikelets/inflorescence branch 9 Length of inflorescence branch, including rachis 10 Length of first glume 11 Length of lobe of rudimentary spikelet 12 Height of flowering culm 13 Diameter of culm near root crown 14 Width near sheath of longest basal leaf 15 Length of inflorescence from panicle tip to first node below flag leaf 16 Length of rachilla of rudimentary floret 17 Number of hairs on second glume 32

-:tCACsJXACA^CAOrHrsJCA Cd CN-CAC»-NOXACN-rHrHNO CNJ XA c rHXACACVJOOrHONOOCNJ o tu) ooooooooocJcD cd OONO-ON^ C^00NO-;t^2-0c' W^^rHrHC^rNOD^XAOON^ c r-i j:f QNXAOOrHONVOCVJCNJ x: •p

CM O

4J XA CA XA CO VA NO 0 -V XA r^ XA O C^ CA 00 NO CA CVJ 00 -^ 00 CTN --t O x/^ r-i CA 0 0 NO 0 0 0 0 CNJ CA u 0 0 0 0 0 0 0 0 0 0 0 0 u CA CNJ r-i r-i r-i 0 CNJ NO r-i C^ CA cd CNJ r-i XA CA XA CVJ CA ^ OS CNl CNJ :3 o^ XA ON CA CA to 0 +^

>> X5 to 73 0 0 r-i ,0 CNJ 00 00 C^ CA 00 CN- NO •H Cd r-i CN- 00 CA CA O CVJ T3 •H XA CNJ CVJ VA XA O NO NO CVJ U X u CNl Cd 'H cd 0 0 0 0 0 0 0 0 0 0 0 73 tt > C -P NO CN- XA 00 CNJ NO C7N 0 Cd cd NO CA NO CN- CN- CO CN- ON NO NO ^ B cd to o CNJ CNl NO NO CVJ 0 •H 0 c c cd cd •H o to u c 0 Cd cd to > 0 O (606 * o (220 ' U JZ o o 0 XA 00 CA CNJ -p CA CJN cH CN- CH C 73 CNl rH r-\ CA r-i 0 0

to .201 ) .061 ) .284 ) .112 ) -p U r-i C 0 0 0 0 0 0 0 0 0 0 0 cd o 0 p. o •H CA J- CN- CNJ NO 0 0 CA XA NO c> O ON c •H 00 00 00 NO 0 CNJ 0 CNJ r-i •H 0 «H sz CNJ CNJ CNJ CA CNJ CH to +^ 0 CNJ +J O C *H O 0 O •H O +^ •H C a OC tH 0 PQ W «M B W CNl CA XA NO 00 C7N O rH 0 0 >-^ MS O r-i CC :D O 0 EH > CHAPTER VI Taxonomic Treatment

Multivariate analyses of morphometric data reveal distinct separation of B. hirsuta. B. gracilis, and B. pectinata. However, all three species exhibit infraspecific populational differences which reflect edaphic and climatic conditions. Clones collected from locations in Table 3 and grown under uniform conditions in the greenhouse and an out­ door plot maintained population characteristics observed in the field, substantiating the morphological separation ex­ hibited in BMD-P7M. In addition, there is not adequate evidence to postulate on-going significant hybridization among any of the species. Examination of herbarium sheets of B. gracilis from localities indicated by (*) below has led the present author to the conclusion that absence of papilli on the second glume, a character commonly used in some dichotomous keys, is an un­ workable character for distinguishing B. gracilis from B. hirsuta and B. pectinata since specimens throughout the range have papilli-based ciliate hairs on the second glume. Rather, emphasis should be placed on extent of tuberculation and number of hairs arising from the tubercles. Both B. hirsuta and B. pectinata are heavily tuberculated, but B. pectinata may have twice as many hairs as tubercles. B. gracilis may 33 34 be heavily tuberculated (usually in far West Texas) but mostly has only one-half the number of tubercles, which us­ ually have more than one hair arising from any one tubercle. The hairs are long (3-4 mm) and usually finer than hairs found on B. hirsuta or B. pectinata. In addition, absence of rachis extension as a bristle is an unworkable character in separating B. gracilis from B. hirsuta and B. pectinata. Again, the relative degree of presence is more useful--B. gracilis frequently has a glume-like extension of the rachis beyond the terminal spikelet; B. pectinata usually has a rachis extension beyond the terminal spikelet with a glume­ like structure on the end; while B. hirsuta has a rachis extension only. Finally, correlation of presence of papilli with presence of glume-like rachis projection is high, but not absolute. Due to the widespread presence of the two above- discussed characters in B. gracilis, they are not useful criteria for postulating present occurrence of hybridization among the three species within their common borders. Rather, they should be taken as evidence of past hybridization and/or evidence of a common ancestor with divergent evolution. This author proposes B. pectinata as a common ancestor to B. gracilis and B. hirsuta, whose evolutionary paths diverged and reproductive barriers established before the Pleistocene era. The advance and retreat of glaciation during the Pleistocene undoubtedly promoted establishment of the many 35 ecotypes of both B. gracilis and B. hirsuta noted by Fults (1942) and Snyder and Harlan (1953) throughout their range. B. pectinata remains in a restricted area of central Oklahoma and east-central Texas and does not exhibit the strong ecotypic variation found in B. gracilis and B. hirsuta. One character was scored (as to degree of presence) on all specimens in this study which was found to be uniform across all biotypes for each species. A tuft of long fine white hairs is present in all B. gracilis at the summit of the rachilla of the rudimentary lobe; it is reduced to a short fuzz in B. pectinata; and totally absent in B. hirsuta. Cytogenetic work in this complex has recently been done for B. hirsuta and B. pectinata by Roy and Gould (1971) but B. gracilis should be given more attention. In addition, a wider sample from the entire distribution range should be taken, particularly in Mexico where B. gracilis and B. hirsuta appear to be more morphologically diverse than in the United States. Maintaining B. pectinata at species level appears to be justified on the basis of this work. Ancient hybridization between B. gracilis and B. pectinata may indeed account for heavy glume tuberculation, rachis extension, and more robust habit observed in B. gracilis in far West Texas. \f

Key to Species

1. Rachis extension beyond terminal spikelet present 2. Rachis extension usually greater than 5 mm and rarely terminating in a glume-like structure. Culm base us­ ually soft, sometimes firm, plants weakly perennial. Culms highly branched, slightly geniculate at lower nodes. Summit of rachilla of rudimentary lobe devoid of pubescence. 1. B. hirsuta 2. Rachis extension to 7 mm and terminating in a glume­ like structure. Culm base firm, plants strongly perennial. Culms cespitose, plants strictly erect. 2. B. pectinata 1. Rachis extension beyond terminal spikelet absent or ap­ pears glume-like. 3. Many (25-35) tubercles with ciliate hairs present on second glume. Inflorescence branches numbering 3-^ (4-5). Summit of rachilla of rudimentary lobe slightly pubescent (short fuzzy hair). 2. B. pectinata 3. Tubercles 0-25, with long (to 3 mm) ciliate hairs present on second glume. Inflorescence branches num­ bering 1-4 (2-3). Summit of rachilla of rudimentary lobe villous with long (3-4 mm) fine hairs. Culms branched and slightly geniculate at lower nodes. 3. B. gracili{^ 1. Bouteloua hirsuta Lag., Var. Cienc. 4: 141. I805. Mexico. Synonomy as per Chase (I95I). Bouteloua hirta Lag., Var Cienc. 4: 141. I805, as synonym of B. hirsuta Lag. Chondrosium hirtum H.B.K., Nov. Gen. et Sp. 1: 176. pi. 59. 1816. Mexico, Humboldt and Bonpland. Actinochloa hirsuta Roem. and Schult., Syst. Veg. 2: 419.I8I7. Based on Bouteloua hirsuta Lag. 37

Eutriana hirta Trin., Gram. Unifl. 240. 1824. Based on Actinochloa hirsuta Roem. and Schult. Atheropogon hirtus Spreng.. Syst. Veg. 1: 293. 1825. Based on Chondrosium hirtum H.B.K. Chondrosium hirsutum Sweet, Hort. Brit. 1: 455. 1826. Presumably based on Actinochloa hirsuta Roem. and Schult. Atheropogon papillosus Engelm., Amer. Jour. Sci. 46: 104. IB43. Beardstown, 111., Geyer. Chondrosium aschenbornianum Nees, Linnaea 19: 692. 1847. Mexico, Aschenbom 33I. Chondrosium foeneum Torr. in Emory, Notes Mil. Reconn. 154. pi. 12. 1848. Valley of the Del Norte (N. Mex., Emory Exped.). Chondrosium papillosum Torr. in Marcy, Expl. Red Riv. 3OO. 1852. Based on Atheropogon papillosus Engelm. Bouteloua foenea Torr. in S. Wats, and Rothr., Cat. PI. Survey W. lOOth Merid. 18. 1874. Based on Chondrosium foeneum Torr. Bouteloua aschenbomiana Griseb. ex Foum., Mex. pi. 2: 137. 1886, as synonym of Chondrosium aschenborn­ ianum Nees. Bouteloua palmeri Vasey, Bull. Torrey Club 14: 9. I887. Name only. Chondrosium drummondii Foum., Mex. PI. 2: 137- 1886. Texas, Drummond 323' Bouteloua hirsuta var. minor Vasey, U.S. Dept. Agr., Div. Bot. Bull. 12: pi. 39. f.2. I89O. (Texas. Reverchon 1153). Bouteloua hirsuta var. major Vasey, U.S. Dept. Agr.. Div. Bot. Bull. 12: pi. 39. f. 3. I89O. Without description. (Austin, Texas, Stiles in 1884). Bouteloua hirta Scribn., U.S. Natl. Herb. Contrib. 2: 531- I894. Based on Chondrosium hirtum H.B.K. Bouteloua hirta var. major Vasey ex L.H. Dewey, U.S. Natl. Herb. Contrib. 2: 53I. I894. Western Texas to Mexico. 38

Bouteloua hirta var. minor Vasey ex L.H. Dewey, U.S. Natl. Herb. Contrib. 2: 53I. 1894. Central Texas.

Bouteloua hirsuta var. palmeri Vasey ex Beal, Grasses N. Amer^ 2~: ^7~ I896. Cultivated, seed collected by Palmer in Mexico.

Bouteloua bolanderi Vasey ex Beal, Grasses N. Amer. 2: 417. I896, as synonym of B. hirsuta var. palmeri Vasey. Highly branched, tufted, weakly perennial. Culms 27-55 (35-40) cm tall, with 1-4 (I-3) inflorescence branches. Blades 1-2 mm wide, usually flat, occasionally subinvolute, with papilla-based ciliate hairs on leaf margins near sheath. Basal leaf length 2.5-34 cm. Inflorescence branch length I.5- 5.0 cm (including rachis projection) and with 14-76 spikelets. Branch rachis projects 4-16 mm beyond terminal spikelet. Spikelets 3.5-7.0 mm in length with papilla-based hairs alongside and on the nerve. Rudimentary lobes present, lo­ cated above fertile floret, with 3 hispid awns. Hair absent from summit of rachilla of rudimentary lobes. Anthers 1.5- 3.5 mm in length. Flowering period June-October. (Fig. 5t Fig. 8). TYPE: Bouteloua hirsuta Lag., Var. Cienc. 4: 141. I805. Mexico. US 7807OI (lectotype). The specimen consists of an inflorescence branch in a remnant folder and appears to belong to a typical B. hirsuta* The holotype was burned with Lagasca*s herbarium; the lectotype was sent from Madrid to Munich by Lagasca in 1820 as part of the original collection (Griffiths. 1912). 39 DISTRIBUTION: North Dakota, Wisconsin, Illinois, south to Texas, Colorado, New Mexico, and Arizona, throughout Mexico to Chiapas (Fig. 1). Diverse soil types. The following specimens were selected from among approximately 1000 sheets examined to establish the geograph­ ical range of the taxon: ARIZONA. Navajo Co., 5 mi S. of Holbrook, 11 Sept 1945, Darrow 33I9 (ARIZ 22343); Pima Co., Ophir Gulch, 4 mi N. and 2 mi W. of Sonoita, I5 Aug I969, Tramontane 80 (ARIZ I8I328). COLORADO. Baca Co., 25 mi S. of Pritchett near Okla. line, 11 July 1947, Porter 4284 (TEX 12483); Boulder Co.. Upper mesas near Boulder, 11 Sept 1920, Hanson C182 (ARIZ 09896). ILLINOIS. Henderson Co., N. of Oquawka, 12 Aug 1934, Chase 5092 (SMU). IOWA. Winneshiek Co., 1 mi S. of Freeport, 8 Sept 1934, Tolstead (NEB I50198). KANSAS. Cowley Co., 9 mi S. of Winfield, 22 Aug I966, Koch I98I (NEB 226601). MINNESOTA. Anoka Co., near Anoka. I3 Oct 1934. Artist 2049. (SMU). NEBRASKA. Hitchcock Co., SE comer of county. 9 Aug 1941, Tolstead 41747 (NEB 223875). NEW MEXICO. Grant Co., Howell's Ridge. Little Hatchet Mtns, 12 Aug 1973, Devender and Spaulding (ARIZ 188447); Quay Co., Conchas canal at Quay County Line, 5 -Aug 1942, Suggs (NMC 38844). NORTH DAKOTA. Anseln, 11 Aug I9I6, Stevens (OKL 151)* OKLAHOMA. Johnston Co.. 1 mi E. of Troy near Rock Creek, 25 Oct 1944, Waterfall 586I (OKLA 2149); Noble Co., 2 mi N. of Perry, 7 Oct 1946, Milton 35 (SMU); Payne Co., 3 mi W. of Stillwater, 5 July 1941, Gibson 80 (ARIZ I7823); Roger Mills Co., in shinnery, 28 June 1939, Engleman 3OO7 (OKL 3O87O). SOUTH DAKOTA. Todd Co., 2 mi N. of Rose Bud, 29 Aug 1935, Tolstead 4-635 (NEB I502I9). TEXAS. Dallam Co., 14 mi E. of Texline on Hwy 296, 25 Aug 1961, Johnston and Walker 6849 (TEX); Limestone Co., 3 mi N. of Groesbeck, Ft. Parker State Park, 9 Oct 1970, Miller 77 (SMU); Terrell Co., I5 mi S. of Sheffield on Blackstone Ranch, 15 June 1949, Webster 274 (TEX I2388); Zapata Co., 1.2 mi NE of Hwy 83 on road to Bustamante, 10 Oct 1954, Tharp and Johnston 541940 (TEX 12434). WISCONSIN. Marquette Co.. Ft. Winnebago, TI3N. R9E, SEC 9» 8 Sept 1948, Seymour IO306 (SMU). MEXICO. Aguascalientes, Mtns above Presa Calles, 30 Aug 1939, Shreve 9251 (ARIZ I782O); Chiapas, 15 mi SE of 40

Teopisca, 21 Aug 1953, Reeder and Reeder 2032 (MEXU 133309); Chihuahua, along Hwy 45 N. of Chihuahua City, 30 Sept 1953. Reeves and Morrow G-37O (SMU); Coahuila, 2 mi SE of Saltillo. 31 Aug 1938, Shreve 85II (ARIZ I78I7); Distrito del Sur, E. of Todos Santos, Sierra de la Laguna, 26 Dec 1947, Carter, Alexander, and Kellogg 2385 (MEXU 60955); Distrito Federal, mixed prairie and woodland near Club Golf de Chapultepec, 4 Sept 1946, Zamora, Paxson. Barkley I6M913 (TEX 214233); Durango, rolling grassy hills, 21 mi SE of Durango, I9 Oct 1966. Gould 12293 (ARIZ 168520); Jalisco, mtns No. of Autlan, 3-5 mi above Mina San Francisco, 30 Sept I96O, McVaugh I9658 (TEX 263746); Nayarit, savannah 21 mi NW of Tepic, road to Santiago, 23 Sept I96O, McVaugh 19435 (TEX 2639II); Nuevo Leon, Galeana, mesa, 30 July 1939, Chase 7673 (TEX 23IO85); Oaxaca, 2 km E. of Zanatepec along Hwy I90, 21 July 1959. King 1881 (TEX 483451); Puebla. 45 mi SE of Mexico City on Hwy 190, 1 Sept 1958, Pratt 760 (TEX 175957); Queretaro, 15 mi SE of San Juan del Rio, 17 Aug 1957, Waterfall 13990 (SMU); San Luis Potosi, in mtns, 19 mi SW of San Luis Potosi on road to Aguascalientes, 19 July 1950, Reeder, Reeder, and Goodding 1391 (MEXU 133398); Sinaloa, Ocurahui, Sierra Surotato, 10 Sept 1941, Harvey 6359 (ARIZ II5079); Sonora. 3 mi S. of Huachinera, 4 Oct I965, Hastings and Turner 65-57 (ARIZ I59287); Tamaulipas, 3 mi S. of Nuevo Leon line on Villagran Linares Hwy, 12 Nov 1959, Johnston and Graham 4665 (TEX 174777); Zacatecas, 71 mi SE of Durango on Hwy 45, 24 Aug 1958, Pratt 603 (TEX 176017). 2. Bouteloua gracilis (H.B.K.) Lag. ex Steud., Nom. Bot. ed. 2. 1: 219. 1840. Based on Chondrosium gracile H.B.K. Actinochloa ciliata Willd. ex Beauv., Ess. Agrost. 41. 1812. Chondrosium ciliatum Willd. Beauv., Ess. Agrost. I58. 1812. Chondrosium gracile H.B.K., Nov. Gen. et Sp. 1: I76. pi. 58. 1816. Mexico, Humboldt and Bonpland. Actinochloa gracilis Willd. ex Roem. and Schult., Syst. Veg. 2: 418. I8I7. Based on Chondrosium gracile H.B.K. Atheropogon oligostachyum Nutt., Gen. PI. 1: 78. 1818. Plains of the upper Missouri (Nuttall). Eutriana gracilis Trin., Gram.Unifl. 240. Based on Actinochloa gracilis Willd. Atheropogon gracilis Spreng.. Syst. Veg. 1: 293. 1825. Based on Chondrosium gracile H.B.K. 41

Eutriana oligostachya Kunth, Rev. Gram. 1: 96. I829. Based on Atheropogon oligostachyus Nutt. Chondrosium gracile var. polystachyum Nees, Linnaea 19s 692. 1847. Mexico, Aschenbom 153. Chondrosium oligostachyum Torr. in Marcy, Expl. Red Riv. 300. I852. Based on Atheropogon oligostachyum Nutt. Bouteloua oligostachya Torr. ex A. Gray, Man. ed. 2. 553. 185^ Based on Atheropogon oligostachyus Nutt. Bouteloua oligostachya var. intermedia Vasey. Grasses U.S. 33. I883. Name only. Bouteloua major Vasey, Torrey Bot. Club Bull. 14: 9. I887. Name only. Bouteloua oligostachya var. major Vasey ex L.H. Dewey, U.S. Natl. Herb. Contrib. 2: 531. 1894. Bouteloua oligostachya var. pallida Scribn. ex Beal, Grasses N. Amer. 2: 418. I896. Mexico, Pringle 407. Bouteloua stricta Vasey, Torrey Bot. Club Bull. 15: 49. 1888; U.S. Dept. Agr., Div. Bot. Bui. 12. pi. 45- I89O. Bouteloua gracilis var. stricta (Vasey) Hitchc, Wash. Acad. Sci. Jour. 23: 454. 1933. Based on B. stricta Vasey. Moderately branched, tufted, strongly perennial. Culms 27-72 cm tall, with 1-4 inflorescence branches. Blades 1 mm wide, usually involute with glabrous margins. Basal leaf length 5-29 cm. Inflorescence branch length 1.5-5.0 cm with 18-96 spikelets. Branch rachis does not project beyond ter­ minal spikelet or extends as sterile glume. Spikelets 3'5- 8.0 mm in length. Glumes unequal, the first 1.0-4.0 mm in length, and the second 2.0-7.0 mm, with 0-25 papilla-based hairs on and alongside nerve. Rudimentary lobes present, lo­ cated above fertile floret, with three hispid awns. A tuft 42 of long pilose hair is present at summit of rachilla of rudimentary lobes. Anthers I.5-3.O mm in length. Flowering period June-October. (Fig. 6, Fig. 8) TYPE: Bouteloua gracilis (H.B.K.) Lag. ex Steud., Nom. Bot. ed. 2. 1: 219. 1840. Type material not examined. DISTRIBUTION: Alberta and Saskatchewan, Montana. Wyoming, Utah, Nevada, Mojave Desert, Arizona, east to Minnesota, Wisconsin, Missouri, Oklahoma. Texas, south through the Mexican highlands to Puebla (Fig. 1). Diverse soil types. Herbarium sheets marked with (*) in the following list are not meant to be a complete accounting of B. gracilis with tubercles, tubercular hairs, and a glume-like rachis projec­ tion, but only to illustrate the extent to which these characters occur. These specimens were selected from among approximately 1000 sheets examined to establish the geograph­ ical range of the taxon: ARIZONA. Cochise Co.. 9 mi S. of Fry, 8 Sept 1944, Gould et al 24o6, (ARIZ IO769); •Coconino Co., near Flagstaff, 21 Aug I926, Porter and Fulton 2885 (ARIZ 91271); Mojave Co., Hualpai Mtn, 19 Sept 1935, Keamey and Peebles, 12657 (ARIZ 91276). COLORADO. Chaffee Co., 8 mi NE of Buena Vista, 14 July 1936, Rollins 1389 (SMU); * La Plata Co., 5 mi W. of Durango, Hess 468 (OKL). IOWA. •Dickinson Co., Lakeville Twp., NWj, SEC 17, Cayler Prairie, 30 June 1955, Thome 16124 (SMU). KANSAS. •Morton Co., 9 mi N. of Elkhart, 7 June I96I. Richards 2505 (SMU). 43

MINNESOTA. Benton Co., Mayhew Creek Valley TiE of East St. Cloud, 31 July 1946, Moore and Huff 18822 (SMU). MISSOURI. Countney, 12 Aug 1894, Bush 788 (OKL). MONTANA. Deer Lodge Co., foothills, 27 Aug 19'^4. Chase 14008 (TEX 9^865). NEBRASKA. Dundy Co. 10 mi N. of Haigler, 28 July 1941. Tolstead 41743 (SMU). NEVADA. •White Pine Co., W. side of Shell Creek Range. 18 Sept 1937, Train 1079 (ARIZ 21261). NEW MEXICO. Sierra Co., Torijillo Creek. 14 Sept 1904, Metcalfe I363 (OKL 3344). NORTH DAKOTA. •McKenzie Co., Theo. Roos. Mem. Pk. on Little Mo. River, 1 Sept I968, Crook 747 (SMU). OKLAHOMA. Carter Co., 2 mi N. and 2 mi E. of Poolville. 9 Aug 1945, Waterfall 6III (OKL 30845); Cimarron Co., 37 mi W. of Guymon, 21 Aug 1927, Stratton 423 (SMU); Comanche Co., Wichita Mtns Wildlife Refuge, 27 June 1948, Orr I96 (SMU); Greer Co., top of earthen dam of Lake Altus, Quartz State Park. 30 Aug I968, Crook 17(^ (OKL 30828); •Payne Co., 2 mi N. of Stillwater, 18 Sept 1940, Hollis 4 (OKL 3O837). SOUTH DAKOTA. Mellette Co., 3 mi E. of Norris, 9 July 1935, Tolstead 4-42 (NEB I50238). TEXAS. •Brewster Co., Sul Ross State College Campus, 2 Oct 1946, Brown GB-7 (TEX 12324); Jack Co., 10 mi SE of Jacksboro, 9 Oct 1949, Turner 1662 (SMU); Randall Co., 4 mi S. of Umbarger, Buffalo Lake Recreation Area, 15 Oct 1955, Williams and McCart 5458 (SMU). UTAH. •Garfield Co., Dixie National Forest, 11.5 mi N. of Escalante on Utah 117, 19 Aug I965, Holmgrem, Reveal, and LaFrance 2545 (KSC); Washington Co., Forest camp 3 mi E. of Pine Valley, 23 Aug 1942, Gould 2053 (ARIZ 08810). WISCONSIN. St. Croix Co., I86I. Hale (SMU). WYOMING. •Hot Springs Co., NW of Thermopolis, Owl Creek Watershed, 21 June 1947, Beetle 4576 (ARIZ 46581). CANADA. Saskatchewan, 20 mi W. of Moose Jaw, campground, 29 Aug 1968, Crook 721 (OKL). MEXICO. Aguascalientes, 8 mi N. of Aguiscalientes, 6 Oct 1955, Emery 264 (TEX I2303); Chihuahua, Sierra de los Organos, 8 Sept 1937, LeSueur 166 (SMU); Coahuila, Sierra de las Cruces, foothills, 8 mi N. of Santa Elena mines, 7 Sept 1940, Johnston and Muller 1028 (TEX); Distrito Federal, Cerrol del Pino, 3 km NNW of Ixtapaluca, 15 Sept I966, Cisneros I23I (TEX); Durango, 20 mi SE of Durango. 20 Oct 1957, Gould and Morrow 79I3 (SMU); Guanajuato, 1 mi S. of Apasco el Alto on steep hillside, 5 Oct 1955, Emery 244 (TEX 12301); Hildago, 16 mi S. of Ixmicuilpan on Hwy 85, 2 Sept 1958, Pratt 763 (TEX 175956); Jalisco, 8 mi SW of Lagos de Moreno on Hwy 80, 25 Aug 1958, Pratt 642 (TEX 175980); Nuevo Leon, 2 mi E. of Nuevo Leon-Coahuila state line, 30 Sept 1955, Emery 123 (TEX); Puebla, 25 mi SE of Perote (5 mi SW of lake), 1 Aug i960, Gould 9265 (TEX I9C98O); Queretaro, 9 mi S. of 4^.

Queretaro. 3 Oct 1955, Emery 226 (TEX 12302); San Luis Potosi, 30 mi S. of San Luis Potosi. 23 Aug 1956, Fearing and Thompson 203 (SMU); Taumalipas, 4 km V.". of Miquihuana, 4 Aug 1941, Stanford, Retherford, Northcraft 647 (;RIZ 10999) (un­ usual morphology); Zacatecas, 15 air mi NE of Estacion Camacho, 23 Sept 1973. Henrickson I349O (TEX). 3. Bouteloua pectinata Featherly, Bot. Gaz. 91: IO3. 1931. Bouteloua hirsuta var. pectinata Cory, Rhodora 38: 405. 193^"^ (based on Bouteloua pectinata Featherly). Very strongly perennial, cespitose. Culms 45-90 cm tall, with 3-6 inflorescence branches. Blades subinvolute to involute with occasional papilla-based ciliate hairs on leaf margins near sheath. Basal leaf length IO-39 cm. Inflores­ cence branches 3.0-6.0 cm long with I8-7O spikelets. Branch rachis usually projects beyond terminal spikelet as a bristle and usually terminates in a glume-like structure. Spikelets 4.O-7.O mm in length. Glumes unequal, the first 1.5-3.0 mm long and the second 2.0-5-0 mm long with papilla-based hairs along nerve. Rudimentary lobes present above fertile floret with three hispid awns. A tuft of short fuzzy hair present at summit of rachilla of rudimentary lobes. Anthers I.8-3.O mm in length. Flowering period late September to November, with inflorescences being exerted up to two months before anthesis. (Fig. 7, Fig. 8). TYPE: Holotype: Oklahoma, Comanche Co., near Ft. Sill, 17 Aug 1929, English 71 (US 1445571), not examined. Isotype: OKLA 13071 Specimen immature. DISTRIBUTION: Central Oklahoma and east-central Texas 45 from Uvalde and Taylor Counties to Tarrant and Limestone Counties. Restricted to well-drained limestone soil. The following specimens were selected from approximately 150 sheets examined to establish the geographical range of the taxon. OKLAHOMA. Carter Co., 1 mi E. and 2 mi N. of Poolville, 13 Aug 1945, Waterfall 6II5 (OKL 30933) (immature); Comanche Co., Fort Sill, 24 Aug I916, Clemens 11474 (OKL 19849)(imma- ture); Murray Co., Piatt National Park, Veterans' Lake, 27 Nov 1947, Classman 1341 (OKL 30925); Oklahoma Co., 2.5 mi W. and 0.5 mi N. of Spencer, 6 Aug 1939, Waterfall 1554 (OKL 30910)(immature); Stephens Co., near Duncan, 9 Sept 1938, Engleman (OKL 30894). TEXAS. Erath Co., 1.8 mi SE of Alexander on Hwy 6, 26 Sept 1950, Cory 58O8O (SMU); Kerr Co., Kerr Wildlife I.'.anage- ment Area, 23 mi NW of Kerrville. 27 Oct 1958, Gould 833I (SMU); McCulloch Co., Brady Mtns, 10 mi N. of Brady, US Hwy 283, 5 Aug 1959, Tharp 56-32 (TEX 172059) (imniature); Parker Co., 5.3 mi SE of Weatherford on Hwy I7I, 30 Sept 1950. Cory 58456 (SMU); Somervell Co., 1.8 m.i NE of Glen Rose, 1 Nov 1953, Shinners I68O3 (SMU); Travis Co., 0.75 mi E. of Cedar Valley, Edwards Plateau, 15 Sept 1949 (SMU); Uvalde Co., Jack Patterson Ranch S. of Leakey on Uvalde Hwy, 10 Aug 1953, Huss 43 (TEX 12403)(immature). 46 Fig. 5. Drawing of B. hirsuta 47 48 Fig. 6. Drawing of B. gracilis 49

TryAt:TrrH LIBKARX 50 Fig. 7. Drawing of B. pectinata 51 52 ^'^''' Su?! (B)'^''fr^ ^^ ^- ^^^^m^ (^). B. ililisuta (B), and B. :Qectiriata (c).~ ' ^ ' -' (approximately X12)— 53

A. LITERATURE CITED ^"^

Barr, A.J., J.H. Goodnight, J.P. Sail, and J.T. Helwig. 1976. User's guide to SAS-76. SAS Institute, Inc. Raleigh, North Carolina. Chase, A. 1951. In ed. 2 of Hitchcock, A.S., Manual of the grasses of the United States. U.S. Dept. Agr. Misc. Publ. 200, (revised). Correll, D.S., and M.C. Johnston. 1970. Manual of the vascular plants of Texas. Texas Research Foundation. Renner, Texas. Cory, V.L. 1936. New names and new combinations for Texas plants. Rhodora 38:405. Dixon, W.J. 1975. Biomedical computer programs. University of California Press, Berkeley. Featherly, H.I. 1931. A new species of grama grass. Bot. Gaz. 91: 103-105. Fults, J.L. 1942. Somatic chromosome complements in Bouteloua. Amer. J. Bot. 29: 45-55. Gaskins, C.T. 1975. SIMPLE, a general program for descriptive statistics and simple correlation analysis. Texas Tech University Computer Center. Griffiths, D. I912. The grama grasses. Bouteloua and re­ lated genera. Contrib. U.S. Nat. Herb. 14: 343-428. Mabry, T.J., K.R. Markham, and M.B. Thomas. 1970. The systematic identification of flavonoids. Springer- Verlag, New York. Rohlf, J.F., J. Kishpaugh, and D. Kirk. 1972. Numerical taxonomy system of multivariate statistical programs. State University of New York, Stony Brook. Roy, G.P., and F.W. Gould. 1971. Biosystematic investiga­ tions of Bouteloua hirsuta and B. pectinata. I. Gross morphology. Southwestern Nat. 15(3): 377-387. Snyder, L.A. and J.R. Harlan. 1953. A cytological study of Bouteloua gracilis from western Texas and eastern New Mexico. Amer. J. Bot. 40: 702-707.